GLAUB Automation & Engineering GmbH needed to automate the labor-intensive assembly of electronic components to circuit boards
ABB’s YuMi can work alongside human workers to precisely fit components into boards with a high degree of accuracy
YuMi can grip and place different components safely and with pinpoint accuracy, while also performing precise quality assurance tasks
In automated assembly, Through-Hole Technology (THT) for components is one of the last labor-intensive bastions of manual labor. THT components have wire “legs” that are usually laboriously inserted by hand through holes in a circuit board ready for soldering.
The automation of manual work processes is one of the core competencies of GLAUB Automation & Engineering GmbH, based in Salzgitter, Germany. With the development and implementation of its own app and software solutions, as well as experience of the operating and processing control level (MES/PLC) in manufacturing IT, GLAUB offers comprehensive know-how as a system integrator. The company has analyzed THT production tasks in detail, identifying the technical obstacles to automating the process.
Previous approaches have largely ignored the delivery and preparation of the components to be placed. However, automation of these two stages is a major challenge. For example, one obstacle is when capacitors are delivered in bulk. Deep-drawn foil blisters, in which the blisters themselves exhibit instabilities and positional inaccuracies, make the process especially difficult. The position of the components in the blister, which is further complicated by the potential twisting of the capacitors around their axis of rotation, further increased the complexity for GLAUB’s technicians and programmers.
Tolerances were also an important issue. These can be component tolerances, mainly in the spacing of the wire component legs, the manufacturing tolerances of the printed circuit boards, as well as the positional tolerances of the printed circuit boards in the workpiece holders or assembly positions. Lastly, the programmers also had to consider the system tolerance resulting from the measurement accuracy of the camera systems used and the repeatability of the robot.
Precision and flexibility required
These numerous different tolerances are compounded by further challenges, mainly related to variations in the products. On the one hand, electronics manufacturers want to create different products, for example, based on basic printed circuit board layouts. On the other, batch sizes decrease as users change their production processes and place smaller orders.
To help meet these challenges and streamline production, the decision was made to introduce ABB’s YuMi dual-arm collaborative robot as part of its assembly line solutions.
Components packaged in deep-drawn foil blisters are delivered to YuMi’s unloading position on a segmented conveyor. The robot achieves short-cycle production by using both of its arms to place components on the circuit boards within a few seconds, eliminating the added space that would otherwise be required for two conventional industrial robots.
In addition, the automation of THT printed circuit board assembly relieves employees of strenuous, monotonous work and makes assembly workstations more effective. YuMi’s compact design simplifies integration into existing plant and line segments, whether it is used at the front of the plant as a “colleague robot,” or is sited within the plant and line structure.
“Diligent” and communicative
Equipped with additional cameras, YuMi becomes a “diligent colleague” in the truest sense of the word, not only placing components with pinpoint accuracy, but also performing precise quality assurance tasks. Precise positioning of the components is not necessary, even during the preparation of the blisters. The robot can reach all positions in the defined workspace, while the 3D cameras transmit the exact pickup points. Only fully assembled printed circuit boards are released for the next work step and, depending on the requirements of the plant and production peripherals, are also reported to the control system as ‘processed’. The robot provides appropriate interfaces for the connection to its working environment. As an option for future applications, the robot controller can be directly connected to other systems, such as the CAD-CAM system of a production planning or work preparation department.
While robot solutions have potential in many areas of electronics production, the assembly of printed circuit boards with THT components using fully automated systems has typically proved to be very complex. In particular, the high degree of setup work for each product cycle can incur costs running into thousands of Euros. By contrast, the solution created by ABB and GLAUB can be implemented with a relatively low initial investment and will pay for itself within twelve months for a three-shift operation.
Other arguments in favor of using YuMi are the minimal space requirements and the rapid convertibility of the solution. Niko Glaub, managing director of the GLAUB group of companies, says: “The overall solution benefits from the fact that YuMi is ‘made for collaboration’ – in other words, it is inherently safe. Compared to conventional industrial robots, its streamlined safety technology allows it to be flexibly integrated into an agile production environment. All this makes it the ideal colleague for assisting workers in THT assembly, a very monotonous activity which up to now has been done completely manually.”